The main issue in the quality of service for satellite transmissions, especially in occasional use transmissions and temporary feeder links, is RF interference from sources like “rogue pirate carriers,” and failed or improperly configured equipment.

To ensure proper performance in satellite transponders in the payload, on-orbit measurements must be made as part of maintenance. This app note focuses on satellite post-launch or on-orbit measurements, and monitoring strategies used for satellite functionality checks when running maintenance routines.

Global Navigation Satellite System (GNSS) based solutions are highly accurate in most cases, but there are circumstances where they are not as effective, such as in dense urban environments with reduced satellite visibility or indoor areas with low signal levels. LTE Location Based Services (LBS) are designed to determine where a device is located to assist in its effectiveness. This Rohde & Schwarz white paper describes limitations of GNSS systems, as well as LTE cellular based alternatives within 3GPP Release 9.

Measuring and monitoring the signals in satellite communications systems is as complex as the tasks of those involved in operating such systems. Satellite operators are normally interested in ensuring that transponder use corresponds to the criteria agreed with users in terms of quality and scope, which also includes the detection of any interference signals. Teleport operators are concerned with making the best possible use of the resources with the communications systems, particularly the space segment. This Application Note describes example measurement principles that cover the above-mentioned applications and for which the NRA range of spectrum analyzers from Narda is particularly suitable.

The introduction of Gallium Nitride High Electron Mobility Transistors (GaN HEMT) in early 2000 has left an undeniable mark on the entire satellite communication landscape. It is now possible for the first time since the introduction of the Solid State Microwave Technology to design and manufacture Power Amplifiers that exceed by several orders of magnitude the reliability, linearity, power density and energy efficiency of all existing technologies, being GaAs, LDMOS, or TWT. By C. Damian, VP Product Line Management and Business Development, and D. Gelerman, President and CEO, Advantech Wireless Inc.

A key limitation of current Ka-band systems is the simultaneous use of Ka-band for both revenue generating user links and backhaul feeder links. The 40 and 50 GHz bands provide opportunity to move commercial high throughput satellite feeder links out of Ka band.

This application note describes methods using an R&S®ZVA network analyzer, one or two R&S®SMB100A signal generators and an R&S®FSW signal analyzer to accurately measure all the key parameters of frequency converters with embedded local oscillator. A commercial satellite up-converter is used as a device under test example.

One of the first optocouplers used for high reliability applications was the simple phototransistor optocoupler. The basic devices were the 4N22, 23, 24 and the 4N47, 48, 49 series of hermetic phototransistor optocouplers in TO‐five type transistor cans made for military applications developed in the early 1970s. However, these devices were never designed specifically for space radiation environments. By Steve Ching and Manor Narayanan, Isolink, a subsidiary of Skyworks Solutions, Inc.